Design and analysis of studies evaluating smoking cessation interventions where effects vary between practices or practitioners.
BACKGROUND: Patients grouped together in practices may share characteristics that cause them to have similar responses to an intervention. Sampling from such groups means that the power of a trial is less than when subjects are selected from the population at random. Knowledge of likely variation in...
| Główni autorzy: | , |
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| Format: | Journal article |
| Język: | English |
| Wydane: |
1996
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